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Compression-development lengths are shorter than tension-development lengths, because some force is transferred to the concrete by the bearing at the end of the bar and there are no cracks in such an anchorage region.

Determine the casting-position modification factor, ψt, for a rectangular beam with b = 16 in. and d = 20 in., three galvanized No. 9 Grade 60 tension-reinforcement bars placed in the top of the beam, and No. 4 Grade 40 stirrups located every 10 in. along the span. Assume 8,000-psi lightweight concrete and a clear cover of 2 in.

A rectangular beam has a cross section of b = 18 in., h = 24 in., and d = 21.5 in. It is reinforced with three No. 8 Grade 60 bars. The concrete strength is 7,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the gross moment of inertia, Ig, for the beam.

A rectangular beam has a cross section of b = 16 in., h = 22 in., and d = 19.5 in. It is reinforced with two No. 7 Grade 60 bars. The concrete strength is 8,200 psi (normal weight). The beam has Grade 60 No. 3 stirrups. Determine the cracked moment of inertia, Icr. The neutral axis location of the cracked beam (measured from the top of the beam) is 3.6543 in.

What is the easiest way to test the bond strength of bars in a laboratory?

Hooked anchorages provide additional anchorage when there is insufficient straight length available to develop a bar.

Compute the maximum bar spacing, s, to control for cracks in a one-way slab with 1.7 in. of clear cover and f​y​ = 66 ksi.

A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 6 No. 6 bars at a depth of 22 in. The top row contains 4 No. 7 bars at a depth of 17 in. Determine the effective (centroidal) depth, d, of the steel.

An elastic calculation gives a good estimate of the concrete and steel stresses at service loads.

Cracks that extend upward as high as the neutral axis and sometimes into the compression zone are likely _______ cracks.